Electron discharge device



Oct. 18, 1932.

P. SCHWERIN 1,882,994

ELECTRON DISCHARGE DEVICE Filed May 29, 1926 I In venfar: Paul Schwerm Patented Oct. 18,. 1932- UNITED STATES A 1,saz,994

PATENT osmos- PAUL SCHWERIN, F YORK, N. Y., ASSIGNOR TO BELL TELEPHONE LABORATORIES, INCORPORATED, 013 NEW YORK, N. Y., A CORPORATION OF new YORK ELECTRON DISCHARGE DEVICE Application filed Kay 29,

formed in the plate surfaces of a high voltage electron discharge device to prevent buckling or warping of'the plate during the evacuation process and normal operation, due to the high temperature maintained in the device Another feature of the invention is a metallic disc, which is supported on the outer surface of the plate electrode and carries a pellet of vaporizable material which is vaporized in the final stage of the evacuation of the device to absorb residual gases. This arrangementforms an eflieient shield to prevent the vapor of the pellet from depositing on the electrode surfaces.

Another feature of the invention consists in bridging the supporting arms of the plate electrode by means of metallic links which prevent expansion of the arms during the heating process and the consequent dislocation of the assembly from the glass stem to which it is frictionally attached.

These and other features of the invention will be clearly understood from a study of the following detailed description in connection with, the accompanying drawing in which Fig. 1 illustrates in perspective an electron discharge device embodying this invention with parts broken away to show the detailed construction, Fig. 2 shows in elevation the plate structure, and Fig. 3 is a cross-sectional view of Fig. 2 on the line 3-3.

The electron discharge device comprises a glass enclosing vessel 10, having its lower end cemented to a cylindrical metal base 11 which carries the contact studs or terminals 12 to which the leading-in Wires from the elec- 1928. Serial No. 112,472.

vided with a projecting rib 1,8, which extends from a point near the top of the plate 16 to the end of the collar 14-and forms a strengthening means for'the supporting arm 17. An integral tab 19 extending from one edge of arm 17 adjacent the corrugated collar is bent over the recess formed by therib 18 and welded to the opposite side of the arm, to

form a bridging member for the metallic arm. This arrangement prevents displacement of the assembled structure from the glass stem due to the expansion of the metal as a result of the excessive heating of the electrodes to remove occluded gases therefrom. Projecting from the free end of each plate surface is a pair of integral tabs which are formed into tubular extensions and project through the apertures in an insulating block 20, preferably of lavite. The end of each tubular extension projecting beyond the upper surface of the block 20 is preferably spun over or otherwise fanned as shown at 21, to rigidly support the insulating block on the plate electrode 16. The plane surfaces of the plate electrode 16 on each side of the rib 18 are provided with divergent triangular embossments 22, the base of each triangle being parallel and adjacent to the longitudinal edge of the'plate surface 16. This arrangement provides a rigid late surface which will not buckle or warp during the operation of the discharge device.

A curved extension 23,is site ends of the insulating tant between the parallel plate surfaces 16 and is provided with an aperture through which a supporting wire 24 slidably extends parallel with the plate electrode 16. This wire supports a continuously wound wire grid 25 which is welded to the wire 24 at the provided at oppoblock 20, equidiscover t int of contact of each successive turn of the grid 25. The sliding upport of the grid b ock supporting wires 24 in the insulating wire 26 which is sealed in the stem 13, and

also supports a metallic hood 33 arranged to e portion of the glass stem between the filament leading-in mm 31 and the grid leading-in wire 26, so that any active material thrown off the filament during operation does not deposit on the glass stem and form a conductive path between the filament and grid leading-m wires. An elon ated aperture 27 in the insulating block 20, orms a well throu h which resilient supporting hooks 28 extend. These hooks are provided with metal sleeves to provide a larger surface for welding the fine resilient wire hooks to the sup orting wire 29 held in the insulating bloc 20. Resiliently supported on the hooks 28, is the M shaped filament 30 which is attached at its lower end to leading-in wires 31, themidpoint of the filament being held by a hook 32 embedded in the top of the glass stem 13. The plate leading-in wire 34 is sealed in the glass stem at a point below the collar 14 and extends within the rib 18 to the surface of the arm 17 to facilitate the welding of the wire to the metal electrode.

Attached to the outer surface of the plate electrode 16 is a metallic disc or shield 35 which is arranged parallel to the plate surface and aflixed thereto by means of integral arms 36 which extend in opposite directions on one diameter of the disc 35 and have the ends of the arms bent and welded to the plate surface 16. A pellet 37 of a vaporizable material, such as magnesium, is centrally attached to the outer surface of disc 35. This arrangement provides an elficient support for the pellet 37 and a shield for the electrodes, since the magnesium vapor emitted by the pellet when vaporized in the final evacuation process of the device is projected toward the wall of the glass vessel 10 to fix or absorb the residual gases in the device and does not deposit on the electrodes.

While the invention has been disclosed with respect to a detailed construction of the discharge device, it is to be understood that various modifications may be made in the structure without departing from the scope of the invention as defined in the appended claims.

What is claimed is:

1. An electron discharge device, comprising an enclosing vessel, a filament, and a plate electrode having at least two triangular embossments on the outer surface thereof, the, base portions of said embossments ex- 1,-asa,oea

plate electrode having a pair of triangular ridges on the longitudinal surface thereof,

the a ices of which face each other.

3. i n electron discharge device, comprising an enclosing vessel a filament, and a plate electrode having a' ongitudinal central. rib and a triangular embossment on each side of said central rib, the bases of each embossment being parallel to the edges of said plate electrode and-said central ri 4. An electron discharge device, comprising a glass vessel, a plurality of electrodes supported therein, one of said electrodes bein g mountedwithin the other with respect to the side walls of said vessel, a vaporizable medium, and a shield between said vaporizablc medium and said other electrode.

5. An electron discharge device, compris ing an enclosing vessel, a filament and a plate electrode supported in, said vessel, a disc parallel with said plate electrode, spacing means between said plate electrode and disc, and a pellet of vaporizable material centrally afiixed to said disc.

6. An electron discharge device, comprising an enclosing vessel, :1 filament and a plate electrode supported in'said vessel, a metallic disc parallel with a surface of said plate electrode having integral arms projecting from said disc and attached to said plate electrode, and a pellet of vaporizable material afiixed to the outer face of said disc.

7. An electron discharge device comprising a vessel having a glass stem, a collar surrounding said stem, a pair of plate electrodes having integral ribs joining said electrodes to said collar, each of said electrodes having a triangular rib on each side of the integral rib, an insulating block attached to said electrodes, and a grid and filament between said electrodes, said grid and filament being supported from said block.

8. In an electron discharge device comprising an enclosing vessel,.a plurality of electrodes mounted therein, a getter material, and a support for said getter material comprising a metallic member having a central portion of relatively large area compared to said getter material positioned between said electrodes and said material and a pair of arms extending from said central portion and aflixed to opposite sides of one of said elec trodes.

In witness whereof, I hereunto subscribe my name this 10th day of May A. D., 1926.

. PAUL SCHWERIN. 

